Browsing by Author "Oliveira, Marisa"
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- Analysis of pharmacy and laboratory reagents stock management in a Portuguese public hospital: a case studyPublication . Sequeiros, José; Pereira, Maria Teresa; Oliveira, Marisa; Ferreira, Fernanda A.The current situation of healthcare units is characterised by the increasing cost of providing the respective care, the consequent deterioration of the financial situation, and the complicated and time-consuming processes. Together with rising demand, they may become factors contributing to a decrease in service demand. Due to this situation, more efficient and effective logistics and supply chain management are widely recognised as one of the main areas for improvement. To provide insight on which areas to improve, several objectives were looked at in this work, including the analysis of the methods and criteria for the selection of medicines in hospital pharmacies, the definition of obstacles to the rational management of stocks, and the analysis of historical data to forecast future demand for a Portuguese public hospital. The study revealed that some of the 1346 products present on the pharmacy’s ERP do not have sufficient historical data to create an accurate forecast. In this context, and with a service level of 95%, 41% of products have a stock higher than what should be the maximum stock, amounting to approximately € 147.908.87 in fixed assets, and 11% of products were at risk of being out of stock at the time. The importance of the evolution of the core information system of hospitals was at stake, ensuring the technological sustainability of the ongoing digital transformation, alignment with ICT rationalisation measures, improvement of customer service, and improvement of the quality of information available to the user.
- Continuous improvement of logistics processes in a production line of electric buses chassisPublication . Gomes, Beatriz Especial; Pereira, Maria Teresa; Oliveira, Marisa; Ferreira, Fernanda A.Nowadays, environmental concerns are deeply rooted in our society. This growing concern is reflected in the strategies implemented by organizations, which are increasingly focused on eco-friendly strategies, not only for its strategic aspect but also for its social responsibility. Therefore, a bus manufacturing company and an automotive company, both located in the north of Portugal, followed this trend by acting in an extremely important area, electric mobility. Since the market is becoming increasingly competitive in these areas it is necessary to ensure the ability of the organization to adapt to its volatility and the efficiency of its processes, in which logistics flows play an important role. It is within the scope of internal logistical flows and processes that this work, developed at the automotive company, in the chassis production line for electric buses, is inserted. The main objective of this project is the continuous improvement of logistics processes, using Lean tools. Firstly, it was necessary to perform a diagnosis and to map the current state of the logistics processes of the electric chassis line, to identify the existing problems and prioritize them in terms of urgency. Based on the Lean philosophy and its inherent tools, such as Standard Work, 5S, Kaizen philosophy and Visual Management, several improvements were presented and implemented, to mitigate the problems that were identified. With the implementation of these improvements in the picking operations, more specifically the picking of the material for the picking boxes, a 44.6% reduction of the time spent on the operation was obtained. Regarding the supply of material to the production line, the duration of this logistic process was reduced by 18.4%.
- Design and implementation of a supplier Kanban system in the automotive sector: an empirical studyPublication . Pereira, Maria Teresa; Lyra, Raquel; Moreira, Miguel Ângelo Lellis; Oliveira, Marisa; Ferreira, Fernanda A.; Silva, Francisco J. G.In an increasingly competitive automotive sector subject to rapid transformation, efficient supply chain management emerges as a critical component for success. In this context, this study explores a Kanban system within an automotive supplier to address the challenges of demand variability and inventory management. Employing an Action Research methodology, the case study unfolds four iterations, each advancing the Kanban solution towards greater efficiency and responsiveness. The initial phase identifies the critical issue of demand variability in part components, prompting a solution that integrates outlier analysis for forecast accuracy. Subsequent iterations refine this approach, evolving from fixed safety margins to a dynamic system based on service levels. A significant breakthrough is achieved in the latter stages, where the demand is aligned with the maximum machine consumption capacity, transitioning from weeks to days in lead time. This adjustment results in a notable reduction of Kanbans, effectively covering forecast peaks and optimizing space utilization. The final solution, entails a reconfiguration of storage racks tailored to the revised Kanban requirements. The outcome demonstrates a significant improvement in inventory management, aligning with the real-time production needs and showcasing the efficacy of a tailored Kanban system in a high variability environment.
- Development of a cost estimation model in a furniture manufacturerPublication . Reis, Francico; Amaral, António; Oliveira, Marisa; Ferreira, Fernanda A.; Pereira, M. TeresaThis work was developed to improve the costing process of new products within the Product Development Department of a furniture manufacturer. It consisted of creating a parametric cost estimation model based on applying simple and multiple linear regressions, considering the existing data of the products produced and their respective costs. The proposed model considers the cost estimation of creating a product that covers the materials and operations costs. The suitability of the different independent variables was studied by applying simple and multiple linear regressions. A set of functions that return an estimate of the cost as a function of these predictor variables was obtained. The model built with the functions obtained provides the materials and operations cost estimation. The results indicated that 75% of the tests performed show an estimation error of less than 2% in the total cost of a product. Incorporating this model in a tool with the purpose of cost estimation brings the ability to predict prices faster, improving the internal process of obtaining costing and enhancing the analytical capacity of the team in the relentless pursuit of cost minimization and value creation.
- Development of a decision support system for freight forecastingPublication . Martins, João P.; Ramos, Filipe R.; Pereira, M. Teresa; Oliveira, Marisa; Ferreira, Fernanda A.The transportation of goods is critical to supply chains, directly influencing efficiency, cost management, and competitiveness. Accurate freight cost forecasting is essential for decision-making, enabling businesses to allocate resources effectively, reduce financial uncertainties, and ensure timely deliveries. This study, conducted in the After-Sales department of a global company, aimed to analyse freight costs per shipment and develop a predictive system based on predefined parameters. Historical data were examined using analytical techniques and time series metrics to identify suitable forecasting methodologies. Specific algorithms, including classical methodologies (exponential smoothing models) and hybrid deep learning models (BJ-DNN model), were tested to evaluate predictive accuracy. Results showed prediction errors ranging from 17% to 56% for exponential smoothing models and from 5% to 27% for BJ-DNN models, demonstrating the superior performance of hybrid approaches. These findings emphasize the potential of predictive models to enhance freight cost forecasting, minimizing error margins and optimizing resource allocation. This research provides a foundation for refining these methodologies, contributing to improved freight cost management and operational efficiency.
- Improvement in planning and resource management for an automotive company’s parts feeding systemPublication . Pereira, Teresa; Xavier, Mariana; Ferreira, Fernanda A.; Oliveira, MarisaThe increasing sophistication of the automotive market and the constant change in customer requirements increases companies’ concern to ensure efficient internal logistic flows in line with Just-In-Time philosophy and Lean principles, to deal with wastes and variability. Variability arises from the growing differentiation of products, from the adoption of multi and mixed model assembly lines, and from the uncertainty in customer demand resulting from the worldwide outbreak of COVID-19. Considering the automotive supplier company as research subject, several problems were found to be compromising the efficiency of one of its in-plant parts’ feeding systems, the most critical problem being the lack of planning and management of resources (human and material) needed to perform the logistic service. Through Action-Research methodology stages, the actions taken culminated in the development of a simulation and decision-support tool for the component supply system resource management and efficiency improvement. The simulations made revealed reliable and adjusted results of workload and workforce to face the variations in customer demand and the existing product mix. After the tool creation, resource planning and balancing was no longer based on managers experience and empirical knowledge only but based on scientific knowledge: concise and reliable data from information systems, measurements, study of times, and literature review on in-plant milk run systems, lean, just-in-time and continuous improvement techniques.
- Logistics flow improvement in a leather goods industryPublication . Pereira, Maria Teresa; Ribeiro, João; Oliveira, Marisa; Ramos, Filipe R.; Ferreira, Fernanda A.This paper presents an optimization case study developed for a leather company, which aims to improve operational performance at the technical team level in routing and apply improvements that impact it. This project aims to create a route optimization model for what were initially intuitive routes. Since the assignment of work hours by the central team varies, there is a fluctuation in the material shipped to each customer. Considering that this fluctuation is relatively small and only happens every quarter, the fixed route system can be considered as functional, needing updating when there is a new time allocation. Thus, the objective is to minimize the total transportation cost, which in this case is provided by the cost per kilometer. To this end, five scenarios, obtained by a decision support tool, were studied. The VRPTW model, together with decisions concerning the routes, namely cross-docking in Orléans, allowed the reduction of costs by more than 30%, maintaining the customer's and company's requirements regarding the service level. These gains refer to one of the scenarios studied, in which it was possible to guarantee all last-mile distribution with three vans, within expected time windows and demands. Although the scenario with the greatest margin for gains is the one that presents a distribution center according to the gravity method, it also requires renting a warehouse in the Perrusson area (area indicated by the gravity method).
- Manufacturing companies industry 4.0 maturity level: a multivariate analysisPublication . Fonseca, Luís Miguel Ciravegna Martins da; Pereira, Teresa; Oliveira, Marisa; Ferreira, Fernanda A.; Busu, MihailPurpose: This research investigates Portuguese manufacturing companies' Industry 4.0 (I4.0) maturity perception level and proposes an index to measure that aim. Design/methodology/approach: This study uses a survey method to gather the companies' perceptions of their I4.0 maturity level and applies subsequent exploratory factor analysis to propose a global I4.0 measurement index. Findings: The research results show that the most critical factors in evaluating the perception level of I4.0 Perception Maturity (IPM) are strategy, leadership, and customer experiences. The result for the Global Index was 53.50%. Hence, the global Index companies' perception of the level of maturity of I4.0 in Portugal is medium. Research limitations/implications: This study encompasses only Portuguese manufacturing organizations (50 valid responses). Moreover, the research is subject to the limitations of the survey methodology, such as possible respondent bias. Practical implications: The Portuguese I4.0 strategy mainly targets small and medium-sized enterprises through a bottom-up approach. Hence, companies need proper methodologies and tools for evaluating I4.0 adoption, identifying their present situation concerning I4.0 and where to focus on improving the process and achieving the intended benefits. Social implications: This research identifies the main perceived benefits and obstacles of adopting I4.0, suggesting avenues for its successful implementation by the Portuguese companies. Originality/value: This study provides a valuable tool for manufacturing companies to identify the factors that need to be improved to create significant growth in the I4.0 Perception Maturity (IPM) index. Therefore, it can support companies in establishing a roadmap for successful I4.0 adoption and improving their performance and competitive position accordingly.
- Manufacturing companies Industry 4.0 maturity level: A multivariate analysisPublication . Fonseca, Luís Miguel Ciravegna Martins da; Pereira, Teresa; Oliveira, Marisa; Ferreira, Fernanda; Busu, MihailThis research investigates Portuguese manufacturing companies’ Industry 4.0 (I4.0) maturity perception level and proposes an index to measure that aim. The research results show that the most critical factors in evaluating the perception level of I4.0 Perception Maturity (IPM) are strategy, leadership, and customer experiences. The result for the Global Index was 53.50%. Hence, the global Index companies’ perception of the level of maturity of I4.0 in Portugal is medium.
- Multicriteria Methodology for Selection of a Personal Electric VehiclePublication . Gomes, Carlos Francisco Simões; Sousa, Francisco; Pereira, Teresa; Oliveira, Marisa; Miranda Torres, Luís NorbertoA methodology that can support the decision process for selecting an Electric Vehicle (EV) is crucial. Considering the quantity, diversity, and complexity of existing EV models, their advantages and disadvantages, and people's increasing concern for sustainability, selecting and buying a personal EV appropriate to one's needs and requirements is not a simple task. Currently, criteria such as price, consumption per 100 km, range, comfort, brand, safety, and technology can be used to analyse available EV models. In this context, the decision-making process can be supported by the Multicriteria Decision Analysis (MCDA), “a method that clearly structures and evaluates complex problems with several alternatives, conflicting criteria, and complex scenarios. The novelty of this paper is to present a hybrid MCDA approach, combining two powerful methods (AHP and PROMETHEE) into a single framework to assist EV selection by any given person who has no multicriteria knowledge. A survey was conducted to define relevant criteria for a private person selecting an EV. The approach was validated for EV selection, considering the available offer within a target value, based solely on available public data, and excluding qualitative criteria. The paper discusses a case study whereby the proposed approach, using both quantitative and qualitative criteria, assists a decision-maker in selecting an EV from a set of alternatives, validated by the decision-maker, proving the importance and relevance of supporting the decision-making process.